SELBSTGETRIEBENES PNEUMATISCHES RAMMBOHRGERAET INSBESONDERE FUER ERDBOHRUNGEN

摘要

In percussion borers in which the drive is inserted into the borehole, the cutter head must displace the earth during the driving in such a way that the friction between the housing and the earth is sufficient to prevent the borer from being repulsed. The shaping of the cone point affects this friction. The percussion borer has a conical cutter head which is acted upon by an impact member which is arranged so as to be pneumatically movable in the housing lying behind the cutter head. The cutter head (2) is formed in a gear shape in cross-section. <IMAGE>